### Commercial **Airplanes** 

# 777 Service Bulletin **SPECIAL ATTENTION Number: 777-71-0055**  Original Issue: June 12, 2014 Revision 1: April 15, 2015 ATA System: 7171 5455 **SUBJECT:** POWER PLANT - Engine Vents and Drains - Pratt & Whitney Engines - Drain Line Replacement and Insulation Blanket Installation Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15 CFR 300-774). An export license may be required before it is used for development, production or use by foreign persons from specific countries. The controller of this data has the individual responsibility to abide by all export laws. 9E991 ECCN: 

## BOEING PROPRIETARY, CONFIDENTIAL AND/OR TRADE SECRET Copyright © 2014 Boeing. Unpublished Work. All Rights Reserved. Treatment of this document and its content is governed by contract with Boeing. Rights to use this document are licensed on a per aircraft basis and such rights may not be transferable. For more information, contact The Boeing Company. Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner, BBJ, DC-8, DC-9, DC-10, KC-10, KC-46, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8, Poseidon and Boeing liveries are all trademarks owned by The Boeing Company; and no trademark license is granted in connection with this document unless provided in writing by Boeing.

Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 1 of 42 3.0Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 2 of 42 **BOEING SERVICE BULLETIN 777-71-0055**

BLANK PAGE**Table of Contents** Revision Transmittal Sheet............................................ 5 Summary...................................................... 7 1. PLANNING INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 A. Effectivity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 B. Concurrent Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 C. Reason. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 E. Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 H. Weight and Balance Changes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 I. Electrical Load Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 J. References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 1. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2. Data Supplied with this Service Bulletin:. . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3. Installation Drawings Used in the Preparation of this Service Bulletin:. . . . . . . . . . . 17 K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 L. Interchangeability and Intermixability of Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . 18 M. Software Accomplishment Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2. MATERIAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 A. Material - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 C. Parts Necessary for Each Airplane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 1. Kits/Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 2. Parts and Materials Supplied by the Operator. . . . . . . . . . . . . . . . . . . . . . . . 21 3. Parts Modified and Reidentified. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 4. Parts Removed and Not Replaced. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 D. Parts Necessary to Change Spares. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 E. Special Tooling - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 F. Special Tooling Necessary to do this Service Bulletin. . . . . . . . . . . . . . . . . . . . . . . 21 3. ACCOMPLISHMENT INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 A. GENERAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 B. WORK INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 FIGURE 1: LEFT STRUT: FORWARD STRUT DRAIN LINE - REMOVAL. . . . . . . . . . . . . . . . 26 FIGURE 2: RIGHT STRUT: FORWARD STRUT DRAIN LINE - REMOVAL. . . . . . . . . . . . . . . 28 FIGURE 3: LEFT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION. . . . . . . . . . . . . 30 FIGURE 4: RIGHT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION. . . . . . . . . . . . 36 APPENDIX A: PART DEMAND INTENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 3 of 42 **BOEING SERVICE BULLETIN 777-71-0055**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 4 of 42 **BOEING SERVICE BULLETIN 777-71-0055**

BLANK PAGE

### Commercial **Airplanes** 

# 777 Service Bulletin **SPECIAL ATTENTION Revision Transmittal Sheet**  **Number: 777-71-0055** Original Issue: June 12, 2014 Revision 1: April 15, 2015 ATA System: 7171 5455 **SUBJECT:** POWER PLANT - Engine Vents and Drains - Pratt & Whitney Engines - Drain Line Replacement and Insulation Blanket Installation This revision includes all pages of the service bulletin. **COMPLIANCE INFORMATION RELATED TO THIS REVISION** Effects of this Revision on airplanes on which Original Issue was previously done: None. **REASON FOR REVISION** This revision is sent to add validation information, related Airworthiness Directive (AD) 2014-20-10 reference, and instructions for lockwire installation on the band clamps supporting the insulation blankets. The data given in Alternative Method of Compliance Notice 777-71-0055-AMOC-01 is included in this revision. These sections were changed: 1. Summary, Background - added validation information. 2. Summary, Compliance - added reference to related Airworthiness Directive (AD) 2014-20-10. 3. Paragraph 1.A.1., Airplanes - listed the affected line numbers, and changed "powered by" to "delivered with" in the Description column of the Group and Configuration Table. 4. Paragraph 1.C., Reason - added validation information and Revision 1 information. 5. Paragraph 1.D., Description - added Revision 1 information. 6. Paragraph 1.E., Compliance - added reference to related AD 2014-20-10. 7. Paragraph 1.F., Approval - updated the alternative method of compliance paragraph to refer to superseding AD 2014-20-10. 8. Paragraph 1.J., References - updated the reference list. 9. Paragraph 2.A., Material and Price Availability - updated retrofit kit information.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 5 of 4210. Paragraph 3.A., General Information - Note 3 was deleted. 11. Figures 3 and 4 - included lockwire installation information in new view G and in the step table, steps 5 and 6. 12. Appendix A - added Boeing Part Demand Intent form. Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity and format changes, to show the location of all content changes. Pages with no vertical lines have no changes. **REVISION HISTORY** June 12, 2014 Original Issue: April 15, 2015 Revision 1:

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 6 of 42 **BOEING SERVICE BULLETIN 777-71-0055**

### Commercial **Airplanes** 

# 777 Service Bulletin **SPECIAL ATTENTION Summary**  **Number: 777-71-0055** Original Issue: June 12, 2014 Revision 1: April 15, 2015 ATA System: 7171 5455 **SUBJECT:** POWER PLANT - Engine Vents and Drains - Pratt & Whitney Engines - Drain Line Replacement and Insulation Blanket Installation BOEING RECOMMENDS THAT EACH OPERATOR EXAMINE THIS SERVICE BULLETIN IMMEDIATELY. **CONCURRENT REQUIREMENTS** None. **BACKGROUND** Accomplishment of the change in this service bulletin will prevent coked hydraulic fluid blockage in the forward strut drain lines. The forward strut drain lines are located adjacent to the hot core zone of the engine. Hydraulic fluid at elevated temperature can coke and block the forward strut drain lines. Forward strut drain lines blocked with coked hydraulic fluid can cause flammable fluid to back up in the strut disconnect assembly and the forward strut dry bay, and spill onto the engine. Flammable fluid at high temperatures that spills onto the engine could result in a fire. Hydraulic fluid contamination, including hydraulic fluid in its liquid, vapor and/or solid (coked) form, of the titanium forward engine mount bulkhead fitting in the strut forward dry bay and the titanium strut disconnect assembly, at high temperature can result in hydrogen embrittlement and in potential cracking of these parts. A cracked bulkhead fitting in the strut forward dry bay can result in the loss of design load capability, which can lead to departure of an engine. Inspection of the forward dry bay and the forward engine mount bulkhead are addressed by service bulletin 777-54-0028. Cracks in the system disconnect assembly may allow any potential fire in the engine area to enter the strut. This could result in an uncontained engine and strut fire. Inspection of the system disconnect assembly is addressed by service bulletin 777-54A0024. Service bulletin 777-54-0023 does a one time inspection of the forward strut drain lines connected to the right (fluid) side of the strut disconnect assembly, with subsequent inspections at regular intervals as indicated in 777 Maintenance Planning Data (MPD) Item Number 54-210-01 and 777 MPD Item Number 54-210-02. Service bulletin 777-54-0027 provides inspections of the forward strut drain lines at intervals shorter than 777 MPD Item Number 54-210-01 and 777 MPD Item Number 54-210-02. Subsequent to the release of the service bulletins mentioned above, Boeing received two additional reports of forward strut drain lines blocked with coked hydraulic fluid. The two airplanes accumulated 24900 and 11800 total flight cycles, respectively. On the first airplane, blockage with coked hydraulic fluid was found in the right (fluid) disconnect drain line at 882 flight cycles from the operator's previous routine strut drain line inspection. On the second airplane, blockage with coked hydraulic fluid was found in the right (fluid) disconnect drain line at 924 flight cycles from the previous forward strut drain line inspection in accordance with service bulletin 777-54-0027. The right (fluid) side of the strut disconnect box was contaminated with hydraulic fluid in both airplanes. Neither airplane had hydraulic fluid contamination in the electrical (left) side of the strut disconnect

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 7 of 42box. Inspection of the forward engine mount bulkhead fitting in the strut forward dry bay were accomplished on both airplanes in accordance with service bulletin 777-54-0028. The first airplane had no contamination of hydraulic fluid on the forward engine mount bulkhead fitting in the strut forward dry bay. The second airplane had hydraulic fluid vapor contamination accompanied by primer blistering on the forward engine mount bulkhead fitting in the strut forward dry bay. This service bulletin gives instructions to replace the strut drain lines connected to the right (fluid) side of the strut disconnect box, install new insulation blankets on the strut drain lines that are close to the hot core zone of the engine, and clean the drain lines connected to the electrical (left) side of the strut disconnect box, the strut forward dry bay and the forward fireseal pan inlet. This will ensure that the drain lines are clean and it will prevent the occurrence of coked hydraulic fluid in the forward strut drain lines. This service bulletin also gives instructions to update the airplane scheduled maintenance program to incorporate 777 Airworthiness Limitation (AWL) 54-AWL-01. This service bulletin will also prevent a possible engine fire hazard and any cracking of the forward engine mount bulkhead fitting and strut disconnect assembly caused by blocked drain lines and contamination with hydraulic fluid at high temperature. As a part of a service bulletin validation program, this change was completed on airplane WA304 by Service Bulletin 777-71-0055 Original Issue before the release of Revision 1 of this service bulletin. The change completed on airplane WA304 by Service Bulletin 777-71-0055 Original Issue is equivalent to the release of Revision 1 of this service bulletin. Airplane WA304 has the configuration of a Group 1 airplane. Boeing Service Related Problem (SRP) 777-SRP-71-0053 is related to this service bulletin. Boeing 777 Maintenance Review Board Report (MRBR) Item Numbers 54-210-01 and 54-210-02 are related to this service bulletin. This table is provided to operators for planning purposes only. Refer to the applicable sections for more information.
**Reference Affected**  **Planning Data** Paragraph 1.A.2., Spares Affected No Spares Affected Paragraph 1.E., Compliance and Paragraph 1.F., Approval Yes AD Related Paragraph 1.H., Weight and Balance Changes Yes Weight and Balance Change Paragraph 1.I., Electrical Load Data No Electrical Load Changed Paragraph 1.K., Publications Affected Yes Publications Affected Paragraph 1.K., Publications Affected No Airplane Flight Operations Affected (Flight CrewOperations Manual and/or FAA Approved Airplane Flight Manual) Paragraph 2.C.1., Kits/Parts Yes Kits/Parts Required Paragraph 2.C.2., Parts and Materials Supplied by the Operator Yes Operator Supplied Material Paragraph 2.F., Special Tooling Necessary to do this Service Bulletin No Special Tooling Required

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 8 of 42 **BOEING SERVICE BULLETIN 777-71-0055 ACTION (PRR 62777-74S)**  Remove the forward strut drain lines connected to the right (fluid) systems disconnect inlet. Clean the left (electrical) systems disconnect, the strut forward lower spar and the forward fireseal pan drain lines. Install new forward strut drain lines and insulation blankets. Do a leak check of the forward strut drain lines for any leak. Update the airplane scheduled maintenance program to incorporate 777 Airworthiness Limitation (AWL) 54-AWL-01. **EFFECTIVITY** 777-200/-300 Airplanes delivered with Pratt and Whitney engines. Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplanes. **COMPLIANCE** The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin mandatory. Federal Aviation Administration (FAA) Airworthiness Directive AD 2014-20-10 is related to this service bulletin. The effective date of AD 2014-20-10 is October 22, 2014. Boeing recommends that the change given in this service bulletin be done within 4000 flight cycles or 750 days after the original issue date of this service bulletin, whichever occurs later. Accomplishment of this service bulletin terminates service bulletin 777-54-0027. Accomplishment of this service bulletin terminates the repeat Part 1 - Strut Forward Dry Bay Hydraulic Fluid Contamination GVI Inspection actions in service bulletin 777-54-0028 if service bulletin 777-54-0028 is done at the same time as this service bulletin or, if a final one time accomplishment of Part 1 - Strut Forward Dry Bay Hydraulic Fluid Contamination GVI Inspection and the applicable corrective actions are accomplished in accordance with service bulletin 777-54-0028 after the incorporation of service bulletin 777-71-0055. **INDUSTRY SUPPORT INFORMATION** Boeing warranty remedies are available for airplanes in warranty as of January 25, 2006. Please refer to Paragraph 2.B., Industry Support Information. **MANPOWER Elapsed Hours**  **Total Task Hours Airplanes**  11.75 14.75 All Airplanes
**MATERIAL INFORMATION** Boeing Supplied Kits/Parts. Refer to Paragraph 2.A., Material - Price and Availability.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 9 of 42 **BOEING SERVICE BULLETIN 777-71-0055**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 10 of 42 **BOEING SERVICE BULLETIN 777-71-0055**

### Commercial **Airplanes** 

# 777 Service Bulletin **SPECIAL ATTENTION Number: 777-71-0055**  Original Issue: June 12, 2014 Revision 1: April 15, 2015 ATA System: 7171 5455 **SUBJECT:** POWER PLANT - Engine Vents and Drains - Pratt & Whitney Engines - Drain Line Replacement and Insulation Blanket Installation BOEING RECOMMENDS THAT EACH OPERATOR EXAMINE THIS SERVICE BULLETIN IMMEDIATELY. **1. PLANNING INFORMATION A. Effectivity**  1. Airplanes This service bulletin is applicable to 777-200/-300 Airplanes delivered with Pratt and Whitney engines, line numbers 2-5, 7-9, 11-13, 16, 21-23, 26-27, 29, 34-40, 43, 45, 50, 52, 57, 59-60, 62, 68-69, 71-73, 75, 77, 79-82, 85, 88, 92-93, 96-97, 104-105, 107-108, 112, 116, 120, 123, 131-132, 134, 137, 139, 141-142, 146, 148, 152, 158-160, 162, 168, 172-173, 178-179, 191, 196, 205, 212-214, 216, 229, 232, 238, 240, 246-247, 254, 259, 264, 278, 280, 282, 286, 288, 290-291, 293-297, 302, 305, 309, 317-318, 322, 338, 340, 344, 347, 349, 352, 356-357, 359, 362, 368, 375, 377, 380-381, 384, 388, 400, 403, 411, 416, 437, 440, 442, 450, 452-453, 458, 460, 481-482, 486, 491, 495, 507, 509, 517, 520, 523, 526, 528, 553, 563, 574, 580, 584, 633, 635, 646, 657, 659, 682, 684, 711, 730, 738, 853, 1005, 1016, 1027, 1090, 1102, 1112, 1117 in 1 Group. The Variable Numbers and Group Information for the applicable airplanes is given below. An equivalent change is on subsequent production airplanes. Refer to PRR 62777-74S for data about this change. Refer to Service Bulletin Index D624W001 Part 3 for Airplane Variable Number, Line Number, and Serial Number data.
**DESCRIPTION CONFIGURATION**  **GROUP** 777 Airplanes, line numbers 2 through 1117, delivered with Pratt and Whitney engines. - 1

Airplane Models: 777-200, 777-300 **Group Variable Number**  1 WA002 - WA017

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 11 of 42**Group Variable Number**  1 WA131 - WA137 1 WA171 - WA175 1 WA206 - WA212 1 WA221 - WA223 1 WA231 - WA232 1 WA241 - WA250 1 WA261 - WA266 1 WA281 - WA283 1 WA301 - WA304 1 WB051 - WB088 1 WB131 - WB148 1 WB151 - WB155 1 WB366 - WB368 1 WB481 - WB484 1 WB531 - WB537 1 WB551 - WB554 1 WB591 - WB597 1 WC111 - WC120 1 WC371 - WC374 1 WC506 - WC508 1 WC581 1 WC586 - WC587 1 WC591 - WC595 2. Spares Affected Examine your Quick Engine Change (QEC) kits for parts or components changed as shown in this service bulletin. If any parts or components are found, refer to Paragraph 2.C., Parts Necessary for Each Airplane, for the recommended use.
**Serial Number Part Number**  -1 QECPW777 A0028 654W0002-53 A0029 654W0002-54 A0049 654W0002-56 -11 QECPW777

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 12 of 42 **BOEING SERVICE BULLETIN 777-71-0055 Serial Number**  **Part Number** A0005, A0011 654W0002-6 A0021, A0035, A0039 654W0002-42 -12, -15, -17, -18, -21, -22 QECPW777
A0041, A0045 654W0002-78 A0016, A0017, A0048 654W0002-33 A0012 654W0002-26 A0004 654W0002-23 A0010 654W0002-24 A0023, A0032 654W0002-51 -4 QECPW777 A0013, A0024 654W0002-29 A0038 654W0002-31 A0025, A0026 654W0002-3001 A0006, A0007, A0008, A0009 654W0002-9
A0014, A0015, A0044, A0046 654W0002-10

A0033 654W0002-73 -14 QECPW777 A0036 654W0002-3013 -5, -9, -7, -13 QECPW777 A0001, A0002, A0003 654W0002-2 A0018, A0019, A0020, A0022, A0027, A0030, A0031 654W0002-37

A0047 654W0002-82 **B. Concurrent Requirements** None.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 13 of 42 **BOEING SERVICE BULLETIN 777-71-0055 C. Reason**  Accomplishment of the change in this service bulletin will prevent coked hydraulic fluid blockage in the forward strut drain lines. The forward strut drain lines are located adjacent to the hot core zone of the engine. Hydraulic fluid at elevated temperature can coke and block the forward strut drain lines. Forward strut drain lines blocked with coked hydraulic fluid can cause flammable fluid to back up in the strut disconnect assembly and the forward strut dry bay, and spill onto the engine. Flammable fluid at high temperatures that spills onto the engine could result in a fire. Hydraulic fluid contamination, including hydraulic fluid in its liquid, vapor and/or solid (coked) form, of the titanium forward engine mount bulkhead fitting in the strut forward dry bay and the titanium strut disconnect assembly, at high temperature can result in hydrogen embrittlement and in potential cracking of these parts. A cracked bulkhead fitting in the strut forward dry bay can result in the loss of design load capability, which can lead to departure of an engine. Inspection of the forward dry bay and the forward engine mount bulkhead are addressed by service bulletin 777-54-0028. Cracks in the system disconnect assembly may allow any potential fire in the engine area to enter the strut. This could result in an uncontained engine and strut fire. Inspection of the system disconnect assembly is addressed by service bulletin 777-54A0024. Service bulletin 777-54-0023 does a one time inspection of the forward strut drain lines connected to the right (fluid) side of the strut disconnect assembly, with subsequent inspections at regular intervals as indicated in 777 Maintenance Planning Data (MPD) Item Number 54-210-01 and 777 MPD Item Number 54-210-02. Service bulletin 777-54-0027 provides inspections of the forward strut drain lines at intervals shorter than 777 MPD Item Number 54-210-01 and 777 MPD Item Number 54-210-02. Subsequent to the release of the service bulletins mentioned above, Boeing received two additional reports of forward strut drain lines blocked with coked hydraulic fluid. The two airplanes accumulated 24900 and 11800 total flight cycles, respectively. On the first airplane, blockage with coked hydraulic fluid was found in the right (fluid) disconnect drain line at 882 flight cycles from the operator's previous routine strut drain line inspection. On the second airplane, blockage with coked hydraulic fluid was found in the right (fluid) disconnect drain line at 924 flight cycles from the previous forward strut drain line inspection in accordance with service bulletin 777-54-0027. The right (fluid) side of the strut disconnect box was contaminated with hydraulic fluid in both airplanes. Neither airplane had hydraulic fluid contamination in the electrical (left) side of the strut disconnect box. Inspection of the forward engine mount bulkhead fitting in the strut forward dry bay were accomplished on both airplanes in accordance with service bulletin 777-54-0028. The first airplane had no contamination of hydraulic fluid on the forward engine mount bulkhead fitting in the strut forward dry bay. The second airplane had hydraulic fluid vapor contamination accompanied by primer blistering on the forward engine mount bulkhead fitting in the strut forward dry bay. This service bulletin gives instructions to replace the strut drain lines connected to the right (fluid) side of the strut disconnect box, install new insulation blankets on the strut drain lines that are close to the hot core zone of the engine, and clean the drain lines connected to the electrical (left) side of the strut disconnect box, the strut forward dry bay and the forward fireseal pan inlet. This will ensure that the drain lines are clean and it will prevent the occurrence of coked hydraulic fluid in the forward strut drain lines. This service bulletin also gives instructions to update the airplane scheduled maintenance program to incorporate 777 Airworthiness Limitation (AWL) 54-AWL-01. This service bulletin will also prevent a possible engine fire hazard and any cracking of the forward engine mount bulkhead fitting and strut disconnect assembly caused by blocked drain lines and contamination with hydraulic fluid at high temperature.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 14 of 42 **BOEING SERVICE BULLETIN 777-71-0055**As a part of a service bulletin validation program, this change was completed on airplane WA304 by Service Bulletin 777-71-0055 Original Issue before the release of Revision 1 of this service bulletin. The change completed on airplane WA304 by Service Bulletin 777-71-0055 Original Issue is equivalent to the release of Revision 1 of this service bulletin. Airplane WA304 has the configuration of a Group 1 airplane. Boeing Service Related Problem (SRP) 777-SRP-71-0053 is related to this service bulletin. Boeing 777 Maintenance Review Board Report (MRBR) Item Numbers 54-210-01 and 54-210-02 are related to this service bulletin. Revision 1 is sent to add validation information, related Airworthiness Directive (AD) 2014-20-10 reference, and instructions for lockwire installation on the band clamps supporting the insulation blankets. **D. Description** Remove the forward strut drain lines connected to the right (fluid) systems disconnect inlet. Clean the left (electrical) systems disconnect, the strut forward lower spar and the forward fireseal pan drain lines. Install new forward strut drain lines and insulation blankets. Do a leak check of the forward strut drain lines for any leak. Update the airplane scheduled maintenance program to incorporate 777 Airworthiness Limitation (AWL) 54-AWL-01. Effects of this Revision on airplanes on which Original Issue was previously done: None. The work in this service bulletin is done in the maintenance zone(s) given below.
**Affected Maintenance Zones Zone**  **Model** 411, 414, 416, 421, 424, 426, 432, 442 777-200, 777-300 **E. Compliance** The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin mandatory. Federal Aviation Administration (FAA) Airworthiness Directive AD 2014-20-10 is related to this service bulletin. The effective date of AD 2014-20-10 is October 22, 2014. Boeing recommends that the change given in this service bulletin be done within 4000 flight cycles or 750 days after the original issue date of this service bulletin, whichever occurs later. Accomplishment of this service bulletin terminates service bulletin 777-54-0027.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 15 of 42 **BOEING SERVICE BULLETIN 777-71-0055**Accomplishment of this service bulletin terminates the repeat Part 1 - Strut Forward Dry Bay Hydraulic Fluid Contamination GVI Inspection actions in service bulletin 777-54-0028 if service bulletin 777-54-0028 is done at the same time as this service bulletin or, if a final one time accomplishment of Part 1 - Strut Forward Dry Bay Hydraulic Fluid Contamination GVI Inspection and the applicable corrective actions are accomplished in accordance with service bulletin 777-54-0028 after the incorporation of service bulletin 777-71-0055. **F. Approval** This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified in this service bulletin comply with the applicable regulations and are FAA approved, as well as European Aviation Safety Agency (EASA)/Joint Aviation Authorities (JAA) approved for all EASA/JAA approved airplanes listed in the service bulletin effectivity. This service bulletin and its approval were based on the airplane in its original Boeing delivery configuration or as modified by other approved Boeing changes. If an airplane has a non-Boeing modification or repair that affects a component or system also affected by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency approval before incorporating this service bulletin. In addition, the Manager of the FAA Seattle Aircraft Certification Office approves the action (i.e. inspection or modification) defined in this service bulletin as an alternative method of compliance to the requirements of paragraph (g) of AD 2014-20-10 . All provisions of AD 2014-20-10 that are not specifically referenced in the above statement remain fully applicable and must be complied with. **G. Manpower** The table below shows an estimate of the task hours necessary to do this change for each airplane. This estimate is for direct labor only, done by an experienced crew. Adjust the estimate with operator task hour data if necessary. The estimate does not include lost time. These are some examples of lost time: • Time to adjust to the workplace • Time to schedule the work • Time to inspect the work • Time to cure the materials • Time to make the parts • Time to find the tools. **Elapsed Hours Task Hours**  **Number of Persons Task**  2.5 2.5 1 Open Access 0.5 0.5 1 FIGURE 1 0.5 0.5 1 FIGURE 2 3.0 6.0 2 Drain Clean 1.0 1.0 1 FIGURE 3 1.0 1.0 1 FIGURE 4 0.75 0.75 1 Leak Check 2.5 2.5 1 Close Access

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 16 of 42 **BOEING SERVICE BULLETIN 777-71-0055 Elapsed Hours**  **Task Hours Number of Persons**  **Task** 11.75 14.75 TOTAL FOR EACH AIRPLANE (a) The estimate assumes that no leaks are found. Additional time may be required if repairs are necessary. **H. Weight and Balance Changes Change in Moment**  **(Pound-Inches) Change in Weight**  **(Pounds) Airplane**  +1055.7 +1.8 All Airplanes
**I. Electrical Load Data** Not changed. **J. References** 1. Existing Data: a. Engineering Change Memo PRR 62777-74S b. Boeing Service Bulletin 777-54-0023, 777-54-0027, 777-54-0028, 777-54A0024 c. Boeing Service Related Problem (SRP) 777-SRP-71-0053 d. Federal Aviation Administration (FAA) Airworthiness Directive (AD) 2014-20-10 e. Service Bulletin Index D624W001 f. Standard Overhaul Practices Manual (SOPM) 20-50-02, 20-60-03 g. Standard Wiring Practices Manual (SWPM) 20-10-11, 20-10-12, 20-10-19 h. 777 Aircraft Maintenance Manual (AMM) 20-11-00, 54-55-01, 71-71-03, 78-31-00 i. 777 Maintenance Planning Data (MPD) Item Number 54-210-01, 54-210-02, 54-AWL-01 j. 777 Maintenance Review Board Report (MRBR) Item Number 54-210-01, 54-210-02 2. Data Supplied with this Service Bulletin: None. 3. Installation Drawings Used in the Preparation of this Service Bulletin:
**Title Drawing Number**  Plumbing Installation EBU 332W3100 Bracket Instl - Airframe 332W3920

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 17 of 42 **BOEING SERVICE BULLETIN 777-71-0055**The table above lists applicable drawings used to prepare this service bulletin. The drawings are not necessary to make the specified changes, and are not supplied with this service bulletin. The drawings may not be applicable to all airplane configurations or operators. **K. Publications Affected** 1. Publications: **Chapter-Section**

**Publication** N71-71 777 Aircraft Maintenance Manual 71-71 777 Illustrated Parts Catalog Section 9 777 Maintenance Planning Data 2. Damage Tolerance Based Structural Inspections: Boeing has evaluated the repairs and/or changes in this service bulletin for effects on Fatigue Critical Structure (FCS) and for changes to Damage Tolerance Inspections (DTI) required in the Maintenance Program. This service bulletin does not affect FCS, therefore DTIs are not necessary. **L. Interchangeability and Intermixability of Parts** Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts. **M. Software Accomplishment Summary** Not affected.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 18 of 42 **BOEING SERVICE BULLETIN 777-71-0055 2. MATERIAL INFORMATION**  **A. Material - Price and Availability** Boeing can supply the kits/parts shown in Paragraph 2.C., Parts Necessary for Each Airplane. Operators are encouraged to share schedule requirements with Boeing for incorporation of the service bulletin. The kits are subject to the terms and conditions of the Boeing standard purchase order acknowledgment. Prices are in United States Dollars. Terms: Net 30 days. Reference this service bulletin and submit your purchase order by one of these methods: 1. Order on-line via ATA Spec 2000 or The Boeing PART Page 2. Fax to (206) 662-7145 **REFER TO THE BOEING PART PAGE ON MYBOEINGFLEET.COM OR CONTACT FIRST RESPONDER AT FR@BOEING.COM FOR THE LATEST REORDER LEAD TIME (ROLT) AND PRICE INFORMATION** 
**Unit Price as of the original issue** **date of this Ser vice Bulletin (US**  **Dollars) ROLT as of the**  **original issue date of this Ser** **vice Bulletin (Cal endar Days)**  **QTY Date**  **Name Kit Number** 

$8,540.00 218 1 June 11, 2014 Top Kit - Pratt & Whit- ney Engines - Forward Strut Drain Insulation Installation 005W3471-1 34 August 7, 2014 18 September 5, 2014 15 October 3, 2014 15 October 31, 2014 15 December 2, 2014 Operators are encouraged to complete the survey provided in APPENDIX A of this service bulletin to help Boeing predict the quantity and timing of the Boeing Supplied Kits. **B. Industry Support Information** Boeing warranty remedies are available for 777 airplanes in warranty as of January 25, 2006. For task hour reimbursement for airplanes in warranty as of that date, send a warranty claim to Boeing Commercial Airplanes Group - Warranties. The kits for airplanes in warranty as of that date will be supplied at no charge. Send a purchase order for the kits to Boeing Spares. Please refer to this service bulletin number and reference the airplane variable number(s) in your purchase order.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 19 of 42 **BOEING SERVICE BULLETIN 777-71-0055 C. Parts Necessary for Each Airplane**  1. Kits/Parts To get the kits/parts shown below, refer to Paragraph 2.A., Material - Price and Availability. **NOTE:** One top kit and the items shown in Paragraph 2.C.2., Parts and Materials Supplied by the Operator, are necessary for each airplane. The Top Kit is divided into Figure kits for each installation figure shown in the table below. **Figure Kit 4**  **3 Top Kit**  1 1 005W3471-1
**ALL**
**KIT 005W3471-1**

**Notes Existing Part**  **Number Name**  **Figure**

**New Part Number 4**  **3 Qty**  (a) 332W3710-22 TUBE ASSY 1 1 332W3710-22 (a) 332W3710-24 TUBE ASSY 1 1 332W3710-24 (a)

- INSULATIONBLANKET FLEXIBLE DRAINLINE 1 1 49M1201-101

(a)

- INSULATIONBLANKET DRAINLINE COVER 1 1 49M1201-103

(a) MS21924J12 UNION, BULK- HEAD 1 1 AS1007J1212(MS21924J12 optional) (a) AS136-12S0177L HOSE, STR TO STR 1 1 AS136-12S2- 0177L (AS136- 12S0177L optional) (a) BACT16BR120612J TEE 1 1 AS4139J120612 (BACT16BR120612J or BACT16BR120612JN optional) (a) AN924-12J NUT, TUBE, BULKHEAD 1 1 AS5178J12(AN924-12J optional) (a) NAS1149C1732R WASHER, PLAIN 1 1 NAS1149C1732R

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 20 of 42 **BOEING SERVICE BULLETIN 777-71-0055 ALL** 
**KIT 005W3471-1**

**Notes Existing Part**  **Number Name**  **Figure**

**New Part Number 4**  **3 Qty**  (a)

- CLAMP, HOSE 1 1 NAS1922-0100-3H (a)

- CLAMP, HOSE 1 1 NAS1922-0125-3H (a)

- CLAMP, HOSE 3 3 NAS1922-0150-3H (a) This part is used in production. 2. Parts and Materials Supplied by the Operator The following parts or materials are necessary to do the change in this service bulletin. Parts and materials in the manuals given in Paragraph 1.J., References, can also be necessary. Examine operator part and material supply to make sure all necessary parts and materials are available.
**Notes Name**  **QTY Part Number / Specification**  LOCKWIRE As Required MS20995NC32 (MS20995C32) (a) LUBRICANT 3 OZ NEVER-SEEZ PURE NICKEL SPECIAL (a) Refer to SOPM 20-60-03 for supplier data.
3. Parts Modified and Reidentified None. 4. Parts Removed and Not Replaced None. **D. Parts Necessary to Change Spares** None. **E. Special Tooling - Price and Availability** None. **F. Special Tooling Necessary to do this Service Bulletin** No special tools or equipment are necessary to do the change in this service bulletin. But, maintenance and overhaul tools in the manuals given in Paragraph 1.J., References, can be necessary. Examine operator tool supply to make sure all necessary tools are available.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 21 of 42 **BOEING SERVICE BULLETIN 777-71-0055**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 22 of 42 **BOEING SERVICE BULLETIN 777-71-0055**

BLANK PAGE**3. ACCOMPLISHMENT INSTRUCTIONS A. GENERAL INFORMATION**  **CAUTION:** KEEP THE WORK AREA, WIRES AND ELECTRICAL BUNDLES CLEAN OF METAL PARTICLES OR CONTAMINATION WHEN YOU USE TOOLS. UNWANTED MATERIAL, METAL PARTICLES OR CONTAMINATION CAUGHT IN WIRE BUNDLES CAN CAUSE DAMAGE TO THE BUNDLES. DAMAGED WIRE BUNDLES CAN CAUSE SPARKS OR OTHER ELECTRICAL DAMAGE. **NOTE:** 1. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for definition of the acronyms. 2. Obey all of the warnings and cautions given in the specified manual sections. 3. This information was deleted. 4. Unless shown differently, these dimensions and tolerances are used: – Linear dimensions are in inches – Tolerance on linear dimensions, other than rivet and bolt edge margins, is plus or minus 0.03 inch – Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch – Angular tolerance is plus or minus 2 degrees – Hole dimensions for standard solid rivets and fasteners are in Structural Repair Manual (SRM) Chapter 51 – Torque Values: — Values for structural fasteners are given in 777 Structural Repair Manual, Chapter 51. — Values for airframe maintenance tasks are included in Chapter 20 of 777 Airplane Maintenance Manual (AMM). — Values for electrical maintenance tasks are included in Chapter 20 of Standard Wiring Practices Manual (SWPM). — Values for engine maintenance tasks are included in Chapter 70 of 777 Airplane Maintenance Manual (AMM). — Non-standard torque values for maintenance tasks are included in the applicable installation step.
5. Use the approved fastener and process material substitutions in accordance with SRM Chapter 51. 6. Refer to the SWPM 20-10-11 and SWPM 20-10-12 for the wire installation procedures, and SWPM 20-10-19 for the wire separation requirements, as accepted procedures. 7. The necessary conditions for selection of clamp type and size are included in SWPM 20-10-12. If any wire bundle support clamp specified in this service bulletin does not make a correct fit on the wire bundle, refer to SWPM 20-10-12 as an accepted procedure to select a clamp that fits correctly.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 23 of 42 **BOEING SERVICE BULLETIN 777-71-0055**8. These work instructions refer to procedures included in other Boeing documents. When the words "refer to" are used and the operator has an accepted alternative procedure, the accepted alternative procedure can be used. When the words "in accordance with" are included in the instruction, the procedure in the Boeing document must be used. 9. The instructions in Paragraph 3.B., Work Instructions and the figures can include operation of tools or test equipment. Boeing Engineering Tool Drawings, the Illustrated Tool and Equipment Manual, and the Special Tool and Ground Handling Drawing Index contain data on versions of the tools or test equipment that you can use. It is permitted to use replaced tools. It is not permitted to use superseded tools. 10. If it is necessary to remove more parts for access, you can remove those parts. If you can get access without removing identified parts, it is not necessary to remove all of the identified parts. Jacking and shoring limitations must be observed. 11. Where the work instructions include installation of a kept part, a new or serviceable part with the same part number can be installed as an alternative to the kept part. 12. This service bulletin includes functional test procedures for the systems changed by this service bulletin. More functional tests can possibly be necessary in accordance with standard maintenance practices because of interruption to other airplane systems. 13. If shading is used, shaded areas in Figures are to separate the non-critical and non-authoritative information from the critical and authoritative information. 14. The compliance times for the actions in Paragraph 3.B., WORK INSTRUCTIONS are in Paragraph 1.E., Compliance. 15. Some steps in the Work Instructions are identified as Required for Compliance (RC). If this service bulletin is mandated by an Airworthiness Directive (AD), then the steps identified as RC must be done to comply with the AD. Alternative procedures for steps not identified with RC can be used if the RC steps can still be done as specified, and the airplane can be put back in a serviceable condition. An Alternative Method of Compliance (AMOC) is not necessary for deviations to steps that are not identified as RC. **B. WORK INSTRUCTIONS** 1. Open the thrust reversers on the left and the right engines. Refer to 777 AMM 78-31-00 as an accepted procedure. 2. RC - Disconnect and remove the forward strut drain lines in accordance with the Figures below: **Right Strut Left Strut**  FIGURE 2 FIGURE 1 3. RC - Clean the left systems disconnect, the strut forward lower spar and the forward fireseal pan drain lines, on the left and the right strut. Refer to 777 AMM 54-55-01, Strut Forward Drain Clean, as an accepted procedure.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 24 of 42 **BOEING SERVICE BULLETIN 777-71-0055**4. RC - Install new forward strut drain lines and insulation blankets in accordance with the Figures below: **Right Strut Left Strut**  FIGURE 4 FIGURE 3 5. RC - Do a leak check of the forward strut drain lines, for any leak, on the left and the right strut, and repair if any leaking is found. Refer to 777 AMM 54-55-01, Forward Strut Drain Line - Functional Check, as an accepted procedure. 6. Close the thrust reversers on the left and the right engines. Refer to 777 AMM 78-31-00 as an accepted procedure. 7. Put the airplane back to a serviceable condition. 8. RC - Update the airplane scheduled maintenance program to incorporate 777 Airworthiness Limitation (AWL) 54-AWL-01.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1: April 15, 2015 25 of 42 **BOEING SERVICE BULLETIN 777-71-0055 FIGURE 1: LEFT STRUT: FORWARD STRUT DRAIN LINE - REMOVAL**  **(SHEET 1 OF 2)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 26 of 42 **BOEING SERVICE BULLETIN 777-71-0055**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for this figure.
**More Data Qty**  **Identification Name**  **Task Step**  from the lower tee. Refer to 777 AMM71-71-03 as an accepted procedure. It may be necessary to remove one or bothclamps and the attaching hardware. Keep any removedclamp and the attaching hardware. 1 332W3710-16 TUBE ASSY Disconnect 1

and the attaching hardware. Refer to 777 AMM 71-71-03as an accepted procedure. Keep the attaching clamp and hardware. 3

- TUBE ASSY Remove 2

**FIGURE 1: LEFT STRUT: FORWARD STRUT DRAIN LINE - REMOVAL (SHEET 2 OF 2)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 27 of 42 **BOEING SERVICE BULLETIN 777-71-0055 FIGURE 2: RIGHT STRUT: FORWARD STRUT DRAIN LINE - REMOVAL**  **(SHEET 1 OF 2)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 28 of 42 **BOEING SERVICE BULLETIN 777-71-0055**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for this figure.
**More Data Qty**  **Identification Name**  **Task Step**  from the lower tee. Refer to 777 AMM71-71-03 as an accepted procedure. It may be necessary to remove one or bothclamps and the attaching hardware. Keep any removedclamp and the attaching hardware. 1 332W3710-16 TUBE ASSY Disconnect 1

and the attaching hardware. Refer to 777 AMM 71-71-03as an accepted procedure. Keep the attaching clamp and hardware. 3

- TUBE ASSY Remove 2

**FIGURE 2: RIGHT STRUT: FORWARD STRUT DRAIN LINE - REMOVAL (SHEET 2 OF 2)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 29 of 42 **BOEING SERVICE BULLETIN 777-71-0055 FIGURE 3: LEFT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION**  **(SHEET 1 OF 6)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 30 of 42 **BOEING SERVICE BULLETIN 777-71-0055 FIGURE 3: LEFT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION**  **(SHEET 2 OF 6)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 31 of 42 **BOEING SERVICE BULLETIN 777-71-0055 FIGURE 3: LEFT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION**  **(SHEET 3 OF 6)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 32 of 42 **BOEING SERVICE BULLETIN 777-71-0055**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for this figure.
**More Data Qty**  **Identification Name**  **Task Step**  (a) 1 AS136-12S2-0177L(AS136-12S0177L optional) HOSE, STR TO STR Install (New) 1

(a) 1 AS1007J1212 (MS21924J12 optional) UNION, BULKHEAD Install (New)

1 AS5178J12 (AN924- 12J optional)NUT, TUBE, BULKHEAD Install (New)

1 NAS1149C1732R WASHER, PLAIN Install (New) (a) 1 332W3710-22 TUBE ASSY Install (New) 2 1 AS4139J120612 (BACT16BR120612J or BACT16BR120612JN optional) TEE Install (New)

**FIGURE 3: LEFT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION (SHEET 4 OF 6)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 33 of 42 **BOEING SERVICE BULLETIN 777-71-0055 More Data**  **Qty Identification**  **Name Task**  **Step** Install with the keptclamp and hardware. 1 332W3710-24 TUBE ASSY Install (New) 3
(a) with the kept clamp and hardware. 1 332W3710-16 TUBE ASSY Connect 4 (a) Make sure that the insulation blanket is oriented between the tube assembly and the pneumatic duct. Maintain a minimum of 0.25 inch clearance around the insulation blanket. 1 49M1201-101 INSULATION BLAN- KET FLEXIBLE DRAINLINE Install (New) 5

Torque to 5.7 in-lb to 6.3 in-lb. Make surethat the screw housing is oriented away from the spray shield, to prevent any damage to the spray shield. 3 NAS1922-0150-3H CLAMP, HOSE Install (New)

at three locations corresponding to each of the three hose clamps. For each of the three hose clamps, wrap the lockwire around the loose end of the clamp strap. Refer to SOPM 20-50-02as an accepted procedure. 3 MS20995NC32 (MS20995C32 optional) LOCKWIRE Install (New)

**FIGURE 3: LEFT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION (SHEET 5 OF 6)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 34 of 42 **BOEING SERVICE BULLETIN 777-71-0055 More Data**  **Qty Identification**  **Name Task**  **Step** Maintain a minimumof 0.06 inch clearance between the insulation blanket and the bleed valve. 1 49M1201-103 INSULATION BLAN-KET DRAINLINE COVER Install (New) 6

Torque to 5.7 in-lb to 6.3 in-lb. 1 NAS1922-0100-3H CLAMP, HOSE Install (New) Torque to 5.7 in-lb to 6.3 in-lb. Maintain a minimum of 0.25inch clearance between the clamp andthe adjacent structure and systems. 1 NAS1922-0125-3H CLAMP, HOSE Install (New)

at two locations corresponding to each of the two hose clamps, and at one location between the two capstans on the insulation blanket. For each of the two hose clamps, wrap the lockwire around the loose end of the clamp strap. Refer to SOPM 20-50-02as an accepted procedure. 3 MS20995NC32 (MS20995C32 optional) LOCKWIRE Install (New)

(a) Refer to 777 AMM 71-71-03 as an accepted procedure, except lubricate the threads with Never-Seez Pure Nickel Special. Refer to 777 AMM 20-11-00 as an accepted procedure.

**FIGURE 3: LEFT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION (SHEET 6 OF 6)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 35 of 42 **BOEING SERVICE BULLETIN 777-71-0055 FIGURE 4: RIGHT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION**  **(SHEET 1 OF 6)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 36 of 42 **BOEING SERVICE BULLETIN 777-71-0055 FIGURE 4: RIGHT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION**  **(SHEET 2 OF 6)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 37 of 42 **BOEING SERVICE BULLETIN 777-71-0055 FIGURE 4: RIGHT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION**  **(SHEET 3 OF 6)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 38 of 42 **BOEING SERVICE BULLETIN 777-71-0055**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for this figure.
**More Data Qty**  **Identification Name**  **Task Step**  (a) 1 AS136-12S2-0177L(AS136-12S0177L optional) HOSE, STR TO STR Install (New) 1

(a) 1 AS1007J1212 (MS21924J12 optional) UNION, BULKHEAD Install (New)

1 AS5178J12 (AN924- 12J optional)NUT, TUBE, BULKHEAD Install (New)

1 NAS1149C1732R WASHER, PLAIN Install (New) (a) 1 332W3710-22 TUBE ASSY Install (New) 2 1 AS4139J120612 (BACT16BR120612J or BACT16BR120612JN optional) TEE Install (New)

**FIGURE 4: RIGHT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION (SHEET 4 OF 6)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 39 of 42 **BOEING SERVICE BULLETIN 777-71-0055 More Data**  **Qty Identification**  **Name Task**  **Step** Install with the keptclamp and hardware. 1 332W3710-24 TUBE ASSY Install (New) 3
(a) with the kept clamp and hardware. 1 332W3710-16 TUBE ASSY Connect 4 (a) Make sure that the insulation blanket is oriented between the tube assembly and the pneumatic duct. Maintain a minimum of 0.25 inch clearance around the insulation blanket. 1 49M1201-101 INSULATION BLAN- KET FLEXIBLE DRAINLINE Install (New) 5

Torque to 5.7 in-lb to 6.3 in-lb. Make surethat the screw housing is oriented away from the spray shield, to prevent any damage to the spray shield. 3 NAS1922-0150-3H CLAMP, HOSE Install (New)

at three locations corresponding to each of the three hose clamps. For each of the three hose clamps, wrap the lockwire around the loose end of the clamp strap. Refer to SOPM 20-50-02as an accepted procedure. 3 MS20995NC32 (MS20995C32 optional) LOCKWIRE Install (New)

**FIGURE 4: RIGHT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION (SHEET 5 OF 6)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 40 of 42 **BOEING SERVICE BULLETIN 777-71-0055 More Data**  **Qty Identification**  **Name Task**  **Step** Maintain a minimumof 0.06 inch clearance between the insulation blanket and the bleed valve. 1 49M1201-103 INSULATION BLAN-KET DRAINLINE COVER Install (New) 6

Torque to 5.7 in-lb to 6.3 in-lb. 1 NAS1922-0100-3H CLAMP, HOSE Install (New) Torque to 5.7 in-lb to 6.3 in-lb. Maintain a minimum of 0.25inch clearance between the clamp andthe adjacent structure and systems. 1 NAS1922-0125-3H CLAMP, HOSE Install (New)

at two locations corresponding to each of the two hose clamps, and at one location between the two capstans on the insulation blanket. For each of the two hose clamps, wrap the lockwire around the loose end of the clamp strap. Refer to SOPM 20-50-02as an accepted procedure. 3 MS20995NC32 (MS20995C32 optional) LOCKWIRE Install (New)

(a) Refer to 777 AMM 71-71-03 as an accepted procedure, except lubricate the threads with Never-Seez Pure Nickel Special. Refer to 777 AMM 20-11-00 as an accepted procedure.

**FIGURE 4: RIGHT STRUT: FORWARD STRUT DRAIN LINE - INSTALLATION (SHEET 6 OF 6)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 41 of 42 **BOEING SERVICE BULLETIN 777-71-0055 APPENDIX A: PART DEMAND INTENT**  **(SHEET 1 OF 1)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 12, 2014 777-71-0055 Revision 1 April 15, 2015 42 of 42 **BOEING SERVICE BULLETIN 777-71-0055**